Aplicação de cinza da casca de arroz, via solo, como fonte de silício em arroz irrigado sob estresse salino

Abstract

Rice is one of the most cultivated cereals in the world. In some regions, situations of losses in irrigated rice production are common. These losses have been occurred due to the water salinization. Si element for rice is related for increasing in plant growth and productivity. The benefits are positive interactions with nitrogen fertilizers, phosphate and potassium, as well as being involved in metabolic or physiological activities of plants under salt and / or water stress. Accordingly, the utilization of Si may result in increased plant's biological ability to withstand the environment's harsh conditions. Thus the aim of this study was evaluate the effect of silicon fertilization derived from rice hull's ashes, in yield and seed quality of rice cultivated under salt stress. The rice cultivar used was IRGA 424. The experimental design was a randomized block in factorial A x B (Factor A-Five doses of rice husk s ash applied to soil: 0 kg ha-1, 500 kg ha-1, 1000 kg ha-1, 1500 kg ha-1 and 2000 kg ha-1, B-Factor Three salt concentrations: 0 mM, 4 mM and 8 mM), with four replications. Silicon fertilization provides an increase in the seed weight per plant. The physiological quality of rice seeds produced is positively influenced by increased levels of silicon in all salt concentrations. Salinity had a negative effect on yield components and physiological quality of seeds produced. The isoenzyme system glutamate oxaloacetate transaminase (GOT) is a complementary tool to assess the physiological seed.